The present invention relates to honeycomb materials, and in particular to a flexible honeycomb structure formable into various non-planar shapes.
The anticlastic properties of standard hexagonal honeycomb and the difficulty of forming such honeycomb into curved or other non-planar shapes is well known. In order to provide a honeycomb structure which can be formed into such non-planar configurations, it has been found necessary to provide the cell walls with excess length by including a curve or corner into the walls. Different types of formable honeycomb are illustrated in the patent to Holland, U.S. Pat. No. 3,227,600 and the patent to Anderson, U.S. Pat. No. 3,616,141, each assigned to the assignee of the present case. However, known methods for designing such a curve into the walls of the honeycomb cells, particularly when graphite yarn laminate is used as the honeycomb material, produces a honeycomb having assymetric cells, unlike standard hexagonal honeycomb, and is desirable to match the characteristics of standard honeycomb with a flexible honeycomb structure.